Source : Webster's Revised Unabridged Dictionary (1913)

Nonmetal \Non"met`al\, n. (Chem.)
   Any one of the set of elements which, as contrasted with the
   metals, possess, produce, or receive, acid rather than basic
   properties; a metalloid; as, oxygen, sulphur, and chlorine
   are nonmetals.

Source : WordNet®

nonmetal
     adj : not containing or resembling or characteristic of a metal;
           "nonmetallic elements" [syn: {nonmetallic}] [ant: {metallic}]

nonmetal
     n : a chemical element lacking typical metallic properties